According to a first prior art, for example described in patent application JP 2014078580 or patent application EP 1509075 or patent application JP 2004128244, there is a known machine for transferring electronic components onto electronic cards, in which sensors are arranged along the conveyor so as to determine the position of the electronic cards advancing along the conveyor.
However, in this first prior art, these sensors are spaced relatively far apart from one another, so that the position of the electronic cards can only be determined at certain locations, at the positions of the sensors.
If an incident occurs between two sensors, neither of the two sensors will detect it, and only the absence of the electronic card will be observed at the second sensor.
The sensors are often positioned strategically along the conveyor, in order to determine the position of the electronic cards at least at these strategic points.
Coverage of strategic locations along the conveyor at the price of a relatively small number of sensors arranged along this conveyor, constitutes a good compromise between coverage of the length of the conveyor, and the complexity and cost of a monitoring system integrating this relatively small number of sensors.